Stabilizer for airplane skis



Jan. 3, 1939. B. W. SZNYYCE 2,142,807

STABILIZER FOR AATRPLANFI SKTS Filed Aug. 15, 1958 -f- 3ER/mno. WSZNYCEH 12 INVENTOR.

ATTORNEY.

Patented Jan. 3, 1939 UNITED smits ATENT OFFICE STABILIZER FOR AIRPLANE SKIS Bernard W. Sznycer, New York, N. Y. Application August 15, 1938, Serial No. 224,893

Claims.

My invention relates to stabilizers for airplane skis and has particular reference to stabilizers for resiliently retaining the skis in the correct position for flying and landing. 5 Skis are used in place of wheels when there is snow or ice on the ground and they are, therefore, made so that they can replace wheels on the shafts of the undercarriage of an airplane. The skis must be prevented from rotation on the shaft in order to assure their proper landing position but, at the same time, they must have a certain degree of freedom to be deflected from the landing position so as to uniformly distribute the pressure on the whole length of the ski when 1 landing. It is desirable, therefore, to provide a resilient means to keep the ski in the neutral position, allowing the ski a limited degree of freedom to be deflected against the resistance of the resilient restraining means, as may be also desirable for reducing their air resistance.

My invention has for its object, therefore, to provide a stabilizer for a ski adapted to resiliently maintain the ski in the correct position for flying and landing and, at the same time allowing certain amount of resilient deflection in either direction from the neutral position. For this purpose I provide a stabilizer between the undercarriage and the ski in the form of two arms rotatively mounted on a special hub on the shaft and connected together by a resilient shock absorber in such manner `that the arms tend to move apart under action of the shock absorber but are retained by a suitable connection with the ski. The arms are also prevented from moving together in one or the other directions although they can move inwardly against the resistance of the shock absorber.

Another object of my invention is to provide a stabilizer which can be mounted on the undercarriage at the inner end of the Wheel shaft and can be slidably connected with the ski so that the latter can be removed and replaced in its' entirety Without disturbing the stabilizer. This is important in view of the fact that skis must be more or less frequently removed for repairs of their bottom surface and it is not desired to disturb the stabilizer for such replacements of the skis.

Still another object of my invention is to provide stabilizers which resiliently retain the ski in its neutral or operative position, allowing at the same time certain limited deflections in either direction from the neutral position. Provision 'for such a double motion is important in order to obtain proper contact ofthe rski With the ground at different landing angles, and it is possible with my rotary mounting rof the stabilizer.

My invention is more fully described in the accompanying specification fand drawing in which: .f5

Fig. 1 is a sectional elevational view of my stabilizer.

Fig. 2 is a sectional end view of my stabilizer. Fig. 3 isvan end view of the stabilizer with the ski on reduced scale. :ifo

My stabilizer consists of arms I and 2 having bores in the upper ends rotatively fitted on a tubular hub 3 which in turn `is mounted on the inner end of a shaft 4 extending from an undercarriage 5 of an airplane (not shown). The hub 31:5 has a flange 0 attached by bolts 'i to a corresponding flange on the inner end of the shaft Where it joins the undercarriage.

The arms are placed side by side and are retained by a ring 9. The free ends of the arms d20 are'pivotally connected at l! to the ends of a shock absorber. The latter may be of any suitable or standard construction, and for the purpose of illustration a tubular telescopic shock absorber is shown consisting of a cylinder l225 with a hollow plunger i3, the air tight connection between the cylinder and plunger being providedbymeans of a packing I4 clamped between the end of the cylinder `and a gland nut l5. A spring IB tends to push the plunger from the cyl- A30 inder.v The plunger has a small hole I1 in the bottom in order to retard the flow of a fluid from the cylinder into the plunger when the latter is moved into the cylinder. The cylinder'may contain air or a suitable liquid such as oil, glycer- 35 ine, a mixture of alcohol and glycerine, etc.

The arms are provided with elongated slots I8 and l0 concentric with the axis of the shaft en gaged by a pin 20 extending from a bracket 2i V on a ski 22. The bracket has a tubular bearing *40 23 for the shaft 4. The slots i8 and I9 extend in the opposite'direction from the pin 20 so that the pin prevents the arms from moving outward under action of the shock absorber. Each ,f4 slot has sufficient length so that the corresponding arm can be deflected inwardly. I have found that satisfactory results are obtained when the slots are of such length as to provide for about 10 deflection of the arms from the neutral po- ,.50 sition. The best practical results are obtained when the angle a for the front arm is made about 10 and the angle b for the rear arm is made 22. The angle b is made larger because in landing Vunder ordinary conditions the rear end of the ski is pressed harder and needs more freedom of movement.

In order to prevent rotation of the stabilizer assembly on the hub, the latter is provided with keys 24 and 25. The corresponding slots or key- Ways 2S, 21 and 26', 21 in the arms are made wider than the keys so that the arms have a limited freedom of rotation in the opposite directions. As is shown in Fig. 1, the keyways extend to the opposite directions in the two arms so that the stabilizer assembly is prevented from rotation in either direction: the right arm 2 cannot turn to the right or outwardly, its keyways resting by the corresponding edges against the keys, but the arm can be turned to the left or inwardly, the keyways having suflicient clearance in this direction, corresponding to the angle b'. The left arm I also cannot move outwardly or to the left, its keyways resting against the corresponding edges of the keys, but the arm l can be moved inwardly, the keyways being of a length correspending to the angle a. It is evident, therefore, that the stabilizer assembly cannot turn as a unit in any direction, but each arm can be independently moved inwardly against the pres- Sure of the shock absorber. The movement is retarded due to the frictional or viscous resistance of the fluid in the shock absorber.

As shown in Fig. 3, my shock absorber can be used with any ordinary airplane ski, including a ski of my own design with a streamlined hood as described in my copendingl patent application Serial Number 224,896. The ski can be easily removed and replaced without disturbing the mounting or adjustment of the stabilizer` It is understood that various details of my stabilizer and the arrangement of parts may be modified without departing from the spirit of my invention as set forth in the appended claims.

I claim as my invention:

l. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of'an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending tothe rear and to the front respectively, means to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward rotation of each arm and to limit its inward rotation, each arm being, thereby permitted to rotate inwardly against the force of the resilient spreading means thereby Apermitting resilient deflection of the skis in either direction from the neutral position.

2. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively, a shock absorber supported between the free ends ci the arms and adapted to yieldably spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, and means to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation,

each arm being thereby permitted to rotate inwardly against the force of the resilient spreading means thereby permitting resilient deflection of the skis in either direction from the neutral position.

3. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft oi an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, the inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively, a shock absorber pivotally supported between the arms and means adapted to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation, each arm being thereby permitted to rotate inwardly against the force of the resilient spreading means thereby permitting resilient deflection of the skis in either direction from the neutral position.

4. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft 0I" an undercarriage, a flange on the hub adapted to be detachably fastened to a corresponding ilange on the undercarriage at the inner end of the shaft, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively, means to resiliently spread the arms apart, means to engage the arms by the ski. so as to limit the outward movement of the arms, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation, each arm being thereby permitted to rotate inwardly against the .force of the resilient spreading means thereby permitting resilient deflection of the skis in either direction from the neutral position.

5. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively,.

means to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, by an angle of at least ten degrees from the neutral position for each bracket, and means on the outward rotation of each arm and to limitl its inward rotation, each arm being thereby permitted to rotate inwardly against the force of the resilient spreading means thereby permitting resilient deilection of the skis in either direction from the neutral position.

6. A stabilizer for an airplane ski comprsing a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively,

the hub to prevent.

means to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, by an angle of at least 10 fo-r the forward extending arm and at least 20 for the rearward arm from their neutral position against, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation, each arm being thereby permitted to rotate inwardly against the force of the resilient spreading means, thereby permitting resilient deflection of the skis in either direction from the neutral position.

7. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and extending to the rear and to the front respectively, means to resiliently spread the arms apart, means to engage the arms by the ski so as to limit the outward movement of the arms, keys fitted in the hub, the arms having keyways for the keys, the keyways being wider than the keys and extending in the same tangential direction as the slots for each arm respectively, the arms when spread apart by the shock absorber being thereby prevented from simultaneous rotation in either direction but each arm having a limited freedom of rotation inwardly against the pressure of the resilient spreading means, the rotation being limited by the length of the slots in the arms for the pin and for the keys, the ski having thereby a limited degree of rotation in either direction from its neutral position.

8. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the Wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and having elongated slots for a pin extending from the ski, means to resiliently spread the arms apart, the slots in the arms extending in the opposite directions from the pin, the pin being thereby resiliently locked between the arms, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation thereby resiliently retaining the ski in its neutral position, the elongated slots being sufficiently long to permit the arms of an inward deflection at a predetermined angle for each arm against the resistance of the resilient spreading means thereby permitting corresponding deflection of the ski in either direction from its neutral position.

9. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotativelyi mounted on the outer end of the shaft, inner and outer arms rotatively mounted on the hub and having elongated slots for a pin extending from the ski, means to resiliently spread the arms apart, the slots in the arms extending in the opposite directions from the pin, the pin being thereby resiliently looked between the arms, and interlocking means between the hub and the arms for preventing their outward rotation and limiting their inward rotation, thereby yieldably retaining the ski and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation thereby resiliently retaining the ski in its neutral position, the elongated slots being sufficiently long to permit the arms of an inward deflection at a predetermined angle for each arm against the resistance of the resilient spreading means thereby permitting corresponding deflection of the ski in either direction from its neutral position.

l0. A stabilizer for an airplane ski comprising a tubular hub adapted to replace the wheel on the inner portion of the wheel shaft of an undercarriage, means to detachably secure the hub to the undercarriage at the inner end of the shaft, the ski being adapted to be rotatively mounted on the outer end o-f the shaft, inner and outer arms rotatively mounted on the hub and having elongated slots concentric with the shaft for a pin extending from the ski, means to resiliently spread the arms apart, the slots in the arms extending in the opposite directions from the pin, the pin being thereby resiliently locked between the arms, and means on the hub to prevent the outward rotation of each arm and to limit its inward rotation thereby resiliently retaining the ski in its neutral position, the elongated slots being suihciently long to permit the arms of an inward deflection at a predetermined angle for each arm against the resistance of the resilient spreading means thereby permitting corresponding deflection of the ski in either direction from its neutral position.

BERNARD W. SZNYCER. 

